1. Field of the Invention
The present invention relates to a method for transferring a web of material from a wound roll onto a winding tube, in which a severing region of the web of material is provided with an adhesive surface and severed. The severing region is arranged to surround a circumferential portion of a carrier roll. The present invention also relates to a winding apparatus having two carrier rolls that form a winding bed, a severing device, an adhesive applicator, and a retaining device.
2. Discussion of Background Information
A method and winding apparatus of the type generally described above have been disclosed, e.g., in German Patent Disclosure DE 40 29 180 A1. These winding apparatuses serve to wind up a web of material, e.g., a paper web, into wound rolls that can be utilized by a user, e.g., a printing plant. As a rule, the length of the web of material is greater than what can be wound onto the wound roll. This happens, e.g., when the web of material is paid out from a larger jumbo or mother roll or when the web of material is produced in a continuous type of production process. In these type configurations, it is necessary, from time to time, to severe the web of material. The end of the web of material is then glued firmly to the fully wound roll, and the leading end of the web of material, i.e., the other side of the severing line, is to be fastened to a winding tube so that a new wound roll may be wound.
In known apparatuses for changing wound rolls, e.g., as disclosed in German Patent Disclosure DE 40 29 180 A1, the web of material is perforated before it contacts the carrier roll. As the web of material continues moving, e.g., into the region of the carrier roll, the web is provided with strips of adhesive that were previously stuck onto a transfer roller at low adhesion. When the web of material is to be severed, a somewhat greater tensile stress is sufficient to tear through the web of material along the perforated line.
A similar procedure is disclosed in European Patent Disclosure EP 0 553 232 B1. Again, the web of material is made sticky prior to contacting the carrier roll and is subsequently perforated in the middle of the adhesive surface.
Finally, as disclosed in European Patent Disclosure EP 0 442 038 B1, adhesive strips are laterally applied next to a perforation line. In this manner, both the perforation and the application of the adhesive strips can be performed by a single device.
In the above-noted devices, the severed edge is, as a rule, not clean. That is, between the perforation holes, the web of material is torn, which does not always result in the desired precision. Moreover, severing accomplished with the aid of a perforation can only be performed on webs up to only certain thicknesses.
In a support roll winder, in which the wound rolls, instead of resting on carrier rolls, are centrally held, e.g., as disclosed in German Patent Disclosure DE 41 15 406 A1, an adhesive strip dispenser is arranged on a traversing carriage, and a severing element in the form of a wheel is arranged to follow the dispenser. The wheel makes a cutting line in the center of the adhesive strip. However, this arrangement runs the risk that the support roller, on which the wound rolls rest, may also be damaged. Furthermore, it requires a relatively large amount of space.